For many utilities, trees are the number-one cause of all unplanned distribution outages. Most damage to electric utility systems during storms is caused by a falling tree or branch that takes power lines out of service. In order to help reduce the frequency of tree damage to utility systems, many utilities implement vegetation management programs as a preventative measure. North American utilities spend $7 billion to $10 billion annually on vegetation management in an effort to prevent service interruptions and safety hazards associated with trees contacting conductors.
Traditionally, vegetation management programs have relied on regular surveying and pruning by arborist teams to help control vegetation around utility systems, but the sheer number of utility lines covering vast distances makes it impractical, in many cases, to send survey teams on the ground. As a result, many utility companies have turned in the past to aerial reconnaissance techniques to provide photographic imagery of their utility systems which can be examined for possible vegetation growth issues. While aerial pictures or helicopter-based line patrol can be examined for vegetation which has grown into the right-of-way for a utility, no satisfactory method or system currently exists which is able to predict vegetation issues before they exist based on estimating vegetation growth relative to an object of interest. While utility companies have traditionally determined vegetation and tree growth as growth of height, stem diameter, or volume, and while these growth rates have been used to predict growth of vegetation which is near to utility right-of-ways, such estimates do not provide growth in relation to the utility (such as a power line), or its clearance space pattern. Unfortunately, growth relative to line clearance is not well defined by vegetation height, diameter, or volume. This lack of knowledge inhibits timely and efficient decision making power concerning the type of mitigation required i.e. mowing, cutting, trimming or tree removal. Consequently, it is often necessary for field personnel to visit the site in person in order to decide the type of maintenance needed to resolve the encroachment. The cost of mitigation is strongly dependant on the type of maintenance required. Ineffective planning due to a lack in prior knowledge concerning the type of maintenance wastes resources and causes more work to be done than is necessary. Therefore, it would be desirable to have an economical, reliable, and easy to use method and system for determining vegetation growth relative to an object of interest, such as a power line conductor, and to use this growth to predict a clearance need in the future in order to more accurately predict vegetation encroachment issues for the utility.